The literacy and early developmental problems facing low-income, preschool children seriously threaten their academic achievement and social adjustment. Such problems are among the most longstanding and critical issues in educational and developmental research and practice. Low-income, preschool children are disproportionately at-risk for developmental lags and poor school performance--problems exacerbated in urban settings with widespread poverty and limited institutional resources. Over the past 10 years, researchers have sought approaches to ameliorate these problems by considering how to link early literacy and learning to broad dimensions of children's psychosocial well-being, health, and socio-cultural context. However, despite the dire need, there have been too few attempts to connect these different areas of inquiry in early childhood development or to examine the interactions between and among them through rigorous multivariate, longitudinal study of evidence-based, integrated curricula. The primary aim of this proposal is to plan a series of studies designed to connect typically disparate areas of research and theoretical frameworks into a comprehensive early literacy curriculum. The multidimensional curriculum will be designed to attend to the needs of the "whole child" and will be built upon empirical research in four focal areas: (1) early reading and language; (2) early numeracy; (3) foundational approaches to learning; and (4) health and physical/social environments. The strength of this proposal is its integration of these areas of research. The plan will provide critical assessment of the intersections among these areas and formulate a comprehensive framework of early literacy and cognitive development, in which reading, writing, and language development become part of a broader conceptualization that integrates models of early numeracy, foundational approaches to learning, health, and physical/social environments. Guided by this broader conceptualization and the extensive early childhood intervention experience of our team, we seek to plan: (1) to develop an evidence-based integrated early literacy curriculum and (2) to conduct a randomized, longitudinal experiment that will comprehensively investigate the efficacy of the integrated curriculum and its relevant components across multiple types of preschool programs and multiple cities, using state-of-the-art research methods.